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Number of results: 6
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Abstract

As of the spring of 2017, the HAŁDY Database is available on the Polish Geological Institute – NRI website. The geodatabase contains information and data on waste mineral raw materials collected on old heaps, industrial waste stock-piles and in post-mining settlers, from the Polish part of the Sudety Mountains. The article presents the types of data and information contained in the geodatabase and the methodology for their collection. As a result of four-year research works, field reconnaissance, archives and geological basic research, 445 objects of former mining and mineral processing were inventoried. There are 403 mine heaps, 16 industrial settlers, 23 stock-piles and 3 external dumps. These are mainly objects after coal mining and metal ores, including post-uranium. The greatest opportunities for the economic use of waste are associated with coal sludge accumulated in settlers of the liquidated Lower Silesian Coal Basin. The material from stone heaps after polymetallic, iron and fluorite ore mining is also easy to use. The issue of the economic use of post-flotation copper ore waste or the recovery of metals (including gold) from dumps of arsenic mining remains open. The limitation here is the efficiency of metal recovery technologies and environmental restrictions. Some of the objects are located in protected areas, which excludes the possibility of waste management. Some stock-piles and heaps should be carefully reclaimed and covered by environmental monitoring, due to their harmful impact on environmental components.
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Abstract

There are approx. 250 coal waste dumping grounds in Poland, yet there are countries in which this number is even higher. One of the largest sites for depositing mining and power plant waste in the Upper Silesian Coal Basin is the Przezchlebie dumping ground. In the article, it is considered as a secondary deposit of raw materials. An assessment of mining waste collected on the Przezchlebie dumping ground was carried out in terms of its impact on the environment and the possibility of its use. Mining waste samples were tested to determine their chemical composition. Physicochemical properties and chemical compositions of water extracts obtained from the investigated waste and groundwater in the vicinity of the dumping ground were analyzed. Due to the fire hazard resulting from the natural oxidation process of chiefly carbonaceous matter and pyrite, the thermal condition of the dumping ground was assessed. The results of the obtained tests confirmed the slight impact of mining waste deposited on the Przezchlebie dumping ground on the environment. The chemical composition, low radioactive activity of waste itself and the results of water extract tests referred to the permissible values according to the Polish Journal of Laws allow for multi-directional waste management. Due to the significant carbon content, the risk of self-ignition poses a significant threat on the dumping ground. Re-mining of the dumping ground and the recovery of raw materials, including coal contained in waste, will eliminate the risk of fire, allowing for a wider use of waste and, at the same time, will allow for other benefits, e.g. in the form of financial resources and the possibility of managing the dumping ground area.
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Abstract

Rare earth metals including yttrium and europium are one of several critical raw materials, the use of which ensures the development of the so-called high technology. The possibility of their recovery in Europe is limited practically only to secondary materials such as phosphogypsum and electronic waste. The article presents the results of our research concerning the development of recovery technology of yttrium and europium from luminophore CRT used lamps. It describes the principle of separation of elements and the test results of cleaning the concentrate. It was shown that the costs of preparing the concentrate according to the proposed technology are lower than the phosphogypsum processing technology and the composition of the resulting product does not contain hazardous substances.
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Abstract

The amount of waste from washing dolomite aggregates increases continuously. Aggregates are washed to remove clayey pollutants.They consist of a large amount of clay minerals and carbonates. Their properties and amount depends on the type of raw material and type of washing technology. Utilization of waste from washing aggregates is common problem and has not been sought out yet. Their usage as the raw material in ceramics might be environmentally friendly way to utilize them. This paper presents technological properties, phase composition and microstructure analysis of materials made of waste sludge from washing dolomite aggregates. Research was divided into three parts: technological properties analysis, phase composition analysis and microstructure analysis. Samples made of waste dolomite sludge were formed in laboratory clay brick vacuum extruder and fired at 900, 1000 and 1100°C. For final materials, apparent density, open porosity, water absorption, compressive strength and durability were examined. Results of technological research suggest the possibility of the application of the waste sludge from washing aggregates in building ceramics technology as bricks materials. Waste sludge from washing dolomite aggregates can be used as the main raw material of building ceramics masses. Without any additional technological operations (e.g. drying or grinding), the material with satisfactory properties was obtained. According to durability results all obtained materials can be used for masonry protected against water penetration and without contact with soil and ground water and also for masonry subjected to passive exposure (F0 – according to the standard EN 771-1).
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Abstract

Results of the investigation of thermal degradation of polyolefins in the laboratory-scale set-up reactors are presented in the paper. Melting and cracking processes were carried out in two different types of reactors at the temperature of 390-420°C. This article presents the results obtained for conversion of polyolefin waste in a reactor with a stirrer. Next, they were compared with the results obtained for the process carried out in a reactor with a molten metal bed, which was described in a previous publication. For both processes, the final product consisted of a gaseous (2-16 % mass) and a liquid (84-98 % mass) part. No solid product was produced. The light, "gasoline" fraction of the liquid hydrocarbons mixture (C4-C10) made up over 50% of the liquid product. The overall (vapor) product may be used for electricity generation and the liquid product for fuel production.
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Abstract

This article investigates possible use of waste gypsum (synthetic), recovered via flue-gas desulfurization from coal-fired electric power plants, in foundries. Energy sector, which in Eastern Europe is mostly composed from coal-fired electric power plants, is one of the largest producers of sulfur dioxide (SO2). In order to protect the environment and reduce the amount of pollution flue-gas desulfurization (FGD) is used to remove SO2 from exhaust flue gases of fossil-fuel power plants. As a result of this process gypsum waste is produced that can be used in practical applications. Strength and permeability tests have been made and also in-depth analysis of energy consumption of production process to investigate ways of preparing the synthetic gypsum for casting moulds application. This paper also assesses the chemical composition, strength and permeability of moulds made with synthetic gypsum, in comparison with moulds made with traditional GoldStar XL gypsum and with ceramic molds. Moreover examination of structure of synthetic gypsum, the investigations on derivatograph and calculations of energy consumption during production process of synthetic gypsum in wet flue-gas desulfurization were made. After analysis of gathered data it’s possible to conclude that synthetic gypsum can be used as a material for casting mould. There is no significant decrease in key properties, and on the other hand there is many additional benefits including low energy consumption, decreased cost, and decreased environmental impact.
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